Abstract
We describe an implementation of Doppler broadening thermometry based upon a room-temperature continuous-wave quantum cascade laser at 9.07 m, coherently phase locked to a thulium optical frequency comb centered at 2 m. The thermodynamic temperature is retrieved from the analysis of multiple-line absorption spectra of the NH band, adopting semiclassical line-shape models and taking into full account the speed dependence of collisional broadening. We demonstrate that a precision of approximately five parts over 10 can be reached as a result of the analysis of only 90 absorption spectra, as acquired as a function of the gas pressure.
- Received 22 March 2013
DOI:https://doi.org/10.1103/PhysRevA.88.012514
©2013 American Physical Society